Combined asbestos and glass fiber yarn



Oct. 11, 1938. D, c, SIMPSON 2,132,702

COMBINED ASBESTOS AND GLASS FIBER YARN Filed May 22, 1937 EN TOR.

A TTORNEYS.

Patented Oct. 11, 1938 UNITED STATES PATENT OFFICE Donald 0. Simpson, Newark, 01110, assignor to Owens-Illinois Glass Comp ny, a corporation of Ohio Application May 22, 1937, Serial No. 144,24! 14 Claims. (01. 111-53) woven cloth, knitted articles, felts, or other fabricated articles, particularly adapted for electrical insulation, packing material, gaskets, friction elements, heat insulation, cements, fillers in fabricated boards, acoustical insulation, battery separators, and various other uses.

Both glass and asbestos fibers taken by themselves have inherent shortcomings which limit their application and use in industry and commerce. Asbestos, for example, is composed of relatively short and weak fibers which prevent them from being fabricated into strong yarns, cloth, 15 and fabrics. Short asbestos fibers have not been fabricated into any type of yarn or fabric without the incorporation of organic fibers such as cotton, or the like, which serve to hold the short asbestos fibers together. Fine wires have also been used for this purpose. Both of these additional components, however, have definite shortcomings and disadvantages, as, for example, the admixture of organic cotton fibers or the like immediately brings down the temperature or fire resistance of the fabric to that of cotton. The incorporation of wires, on the other hand, prevents the use of the product as an electrical insulation. The use of metal wires or the like is also inferior from the point of view of pliability, flexibility, cost, ease of manufacture, and feltability between the metal wires and the asbestos.

Ordinary glass fibers also have serious shortcomings and limitations in their fabrication into woven fabrics. These limitations are generally traceable to the inherent nonstretchability of glass fibers, the stretchability being limited to one or two percent or so, according to the exact fiber diameter, the type of glass, and the perfection of the fiber. When a series of glass threads are fed into a conventional loom to form a warp, the sudden stresses and loads inherent in a loom are concentrated in the tightest threads which cannot carry the entire load themselves and, therefore, tend to break rather than stretch. Of course, whenever an end or thread breaks in a loom, the entire operation must be stopped and the broken end fed through again before the weaving may be resumed. A similar condition exists when ordinary glass yarns or threads are fed into the weft or filler of a fabric. Moreover, fabrics composed solely of glass fibers, especially if made particularly sheer or thin, have considerably less resistance to folding or creasing than ordinary fabrics. If the fabric is flexed to any 55 degree, or creased, it tends to crack or break and fall apart. Merely reducing the diameter size of the glass fibers does not necessarily cure this condition because, as the fiber diameter is reduced, so is the radius of curvature around which the fibers have to be bent. That is to say, the fibers of the warp are bent around the fibers of the filler and if they are bent around a small enough radius of curvature, the fibers of the warp are cracked and broken. The same condition, of course, obtains when the fibers of the filler are bent around the fibers of the warp.

Another difficulty caused by the inherent nonstretchability of the glass fibers, is the concentration of stresses induced in the outermost fibers at a fold or flexure in the cloth. The glass fibers being more or less unyielding in and of themselves, prevent the load caused by a fiexure or creasing from being distributed uniformly throughout the body of fibers to permit their full combined strength to be brought into play.

I have discovered that the above mentioned individual shortcomings of the asbestos and glass fibers may be overcome by a combination of the two, and that a superior product, having properties superior to any of the individual properties of the ingredients, may be produced by a combination of the two types of fibers.

An object of the invention is the provision of a fabric which is flexible, soft, strong, and completely fireproof, fire resisting, rot proof, and chemically resistant.

Another object of the invention is the provision of a fabric composed of inorganic fibers which may be fabricated into felt or interwoven tape suitable for electrical, heat and/or sound insulation.

Another object of the invention is to utilize the softness, pliability and yieldability more naturally inherent in the asbestos fibers in combinationwith glass fibers, which are much stronger and longer than the asbestos fibers. The individual glass fibers are sufilciently fine and long so that they may be intertwisted or interfelted with the asbestos fibers to form strong yarns which may be safely subjected to the rigors of a conventional loom. The asbestos fibers serve as cushions for the adjacent glass fibers to assist in the distribution of loads throughout the glass fibers, and to lend yieldability and pliability and strength to the final fabric.

In addition, if the glass fibers have been intertwisted or interfelted with the asbestos fibers, this arrangement will prevent the individual glass fibers from being laid out in straight lines, but, on the contrary, will permit them to assume helithe fact that the asbestos material may be comparatively rough, and when composed of a mass more equally.

Other objects and advantages of the present invention will become apparent from the following description taken in conjunction with the drawing, in which:

Fig. 1 is an elevational diagrammatic view of an apparatus adapted to produce yarns composed of asbestos and glass fibers; V,

Fig. 2 is a fragmentary diagrammatic plan view of a portion of the apparatus illustrated in Fig. 1;

Fig. 3 is a fragmentary elevational diagrammatic view of another form of apparatus adapted to produce yarns composed of asbestos and glass fibers;

Fig. 4 is a fragmentary diagrammatical elevational view of a modified embodiment of the present invention; and

Figs. 5, 6, 7, 8 and 9 are fragmentary perspective views of yarns or fabrics which may be made in accordance with the present invention, and which will be explained more fully hereinafter.

In practicing the present invention, resort to at the same time, are not so fine that the cost or speed of manufacture is prohibitive. However,

over a considerable length of these fibers. Accordingly, I preferably use glass fibers having may be produced by facture.

In producing yarns of combined asbestos and glass fibers, it is possible to pick' them apart and Intermix them together with a which the stresses placed in the yarn so that they may 2.

interwoven into fabrics having any desired conan taneously as belt. Various methods of this type of incorporation. when used with cotton fibers, have been illustrated and described, for example, in the Heany Patent Nos. 1,155,812, 1,155,813, and 55 1,071,676.

A yarn made in accordance fibers having a covering I! of intermatted as- 60 bestos fibers.

It is also possible to use for the yarn H a glass sliver composed of a multiplicity of glass fibers fibers 45 fibers, here again the glass fibers serving to carry the load of the yarn as a whole, and the intertwisted asbestos strip of paper or felt serving to form a cushion for the glass yarn, which is ordinarily nonstretchable. When using such a combination for a friction element or fabric, it may be desirable to pull the glass threads so as to be embedded more or less into the intertwisted asbestos paper or felt, leaving the asbestos fibers exposed more predominantly on the outer surface of the yarn where it may serve as the primary friction element.

Another method of incorporating asbestos and glass fibers into yarns is illustrated in Fig. 6 and involves producing asbestos yarns or rovings 40 in the conventional manner and intertwisting these with the yarns 4| composed solely of glass fibers. Ordinarily, the asbestos yarns are not composed of pure asbestos fibers, especially if the asbestos is of the short fiber variety, in which case a small amount of organic fibers, such as cotton, wool, hemp, jute or the like, is incorporated therein in order to provide strength to the yarn during fabrication. In this event, the presence of the organic fibers does not hinder the temperature resistance of the finished fabric after it has been combined with the glass fibers, for in this event the glass fibers are present and may carry the tensile load even though the organic fibers may be burned out or otherwise destroyed as, for example, by acid, rotting, or the like. In other words, the use of the organic fibers is principally for the purpose of assisting the fabrication of the article rather than being present as a required element after the fabric has been completed.

As another method of incorporating asbestos fibers directly in with the glass fibers to produce a yarn, I may use the apparatus illustrated in Fig. l in which reference character l5 designates an apparatus for attenuating a multiplicity of glass fibers by gaseous mediums, such as steam, air, or the like. This apparatus I5 may be constructed and operated in accordance with the disclosure in the British patent applied for by Triggs, No. 428,720. Mounted under the forming apparatus I5 is a collecting device I6 composed of a traveling screen or perforated surface H, which may be mounted upon an open ended hollow drum i8, revolving upon the shaft l9. Extending into and mounted within the drum l8 and underneath the upper portion of the screen I1 is a suction chamber 20 adapted to draw the gases emanating from the forming apparatus 15 and serving to retain the fibers 2| in matted formation more firmly upon the screen I1. A blower or other suction means 22 may also be provided in conjunction with the suction chamber 20 and serves to exhaust the gases from the chamber.

After the fibers have been arrested upon the belt or screen l1 in the form of a web 30, they are drawn therefrom into sliver form or yarn 23 through the trumpet or guiding device 25, and then over the rotating spool 26 where they are collected into a package. The roll '21 may be used in order to change the direction of the yarn 23, although in practice this is unnecessary. A traversing eye or trumpet 28 may also be provided in order to traverse the yarn across the spool 26 and thus form a uniformly built up package.

Arranged under the web 30 of the fibers as they are being drawn into a silver, is a dofier belt 3i leading from a suitable asbestos carding device (not shown) and conveying a multiplicity of asbestos fibers 33 arranged and combed in more or less parallel longitudinal position upon the belt 3 i whereby they may be introduced into the web 30 of glass fibers and incorporated therein to form a mutually interfelted product of combined glass and asbestos fibers. With this arrangement, it will be noted that prior to the incorporation of the asbestos fibers with the glass fibers, the latter are open and in an arrangement facilitating the incorporation of the asbestos fibers. From here the glass fibers are drawn or drafted into a more campact yarn 23, the adjacent glass fibers being drawn together, closing up the intervening spaces, and permitting the interjacent asbestos fibers to be seized and interfelted therewith in a compact, mutually interfelted coherent yarn. This yarn 23 is then drawn through the trumpet 25 and wound upon the spool 26 from which it may be unwound and if desired, twisted into a more compact denser yarn.

If desired, a spray gun 35 may be provided at any suitable point as, for example, over the web 30, in order to apply a suitable binder or adhesive to the fibers of the finished yarn.

If desired, the yarn of combined asbestos and glass fibers may also be drafted by suitable drafting means and a plurality of the yarns, drafted or not, may be intertwisted to form ply yarn such as the one illustrated in Fig. 5.

Referring now to Fig. 3, I have illustrated a modification of the apparatus shown in Figs. 1 and 2, the principal difference being that in the apparatus illustrated in Fig. 3 the asbestos fibers are distributed over the glass fibers as they lie in web form, prior to being drafted into a sliver. In the drawing, reference character designates a glass filament or fiber forming apparatus adapted to produce a multiplicity of fine fibers 46 by means of a gaseous blast emanating from the blowers 41. The gaseous blast carries the fibers downwardly and deposits them upon a perforated or foraminous screen belt 48 upon which the fibers accumulate in intermatted or web form. The gaseous blast passes directly through the screen belt 48 and into a suction chamber 49 which may be used to assist the deposition and retention of the fibers upon the belt 48. A blower B, communicating with the chamber 49, may also be provided in order to exhaust the gases from the suction chamber. As the fibers 46 lie upon the belt 48 in the form of a thin mat or web 50, they may be sprayed, if desired, with a suitable adhesive or binder by means of an applicator 5| of any suitable design. In practice, the adhesive application may be made before or after deposition of the glass fibers into web form, or during the drafting operation into sliver form.

Mounted over the web 50 is a feeder 53 adapted to deposit a multiplicity of asbestos fibers 54 in a layer overlying and partially intermatted with the web 50. The feeder 53 may be of any suitable type, as a vibrating belt or the like. A hopper 55 containing the asbestos may be mounted over the feeder 53; and the hood or chute 56 may also be provided in order to assure the proper distribution and deposition of the asbestos fibers 54 upon the web 50.

After the web 50 has been coated with asbestos fibers the mass is drawn up and collected through a trumpet 51 into a sliver form, the individual glass fibers tending to be interlaced and intermingled with the admixed asbestos fibers.

From the trumpet the slivers may then be passed over the diablo-shaped rolls 5! having a result again is a yarn composed of intermingled glass and asbestos fibers, which may be handled with any of the usual processes in the formation of intertwisted yarns, ply yarns, and interwoven fabrics.

a web 66 of fine glass fibers has been arrested and collected. The web 65 is drawn into the form of a sliver through the trumpet 66 and then over a suitable folding device 81 which may be in the form of a diabloshaped roll having a V-shaped, cardioid, or heart-shaped cross-section exposed to the sliver.

Mounted in conjunction with the roll 51 is a guide 68 arranged at the opening of the V and adapted to guide anasbestos roving, yarn, or thread 69 thereunder and into the partially open fold of the glass sliver. The sliver is advanced in semifolded form beneath a guide 12 The folding device tion of compacting the glass sliver, which more ticn with the present invention.

All of the fibers, or, if desired, either one or both may be composed of combinations of the two.

Modifications and variations may be resorted to within the spirit and scope of the present invention.

5. A yarn comprising asbestos fibers, inter- 8. A ply yarn comprising asbestos roving and threads composed of fine, long, attenuated glass fibers intertwisted with said roving.

9. A yarn comprising athread of long, attenuated glass fibers,

bestos fibers overlying the surface of and coating said glass thread.

a covering therefor.

13. An interwoven fabric of yarns composed of asbestos fibers and combined long, fine attenu- 'ated glass fibers. 

